Add performance improvements section to release notes (jesseduffield#3922)

- **PR Description**

- **Please check if the PR fulfills these requirements**

* [ ] Cheatsheets are up-to-date (run `go generate ./...`)
* [ ] Code has been formatted (see
[here](https://github.com/jesseduffield/lazygit/blob/master/CONTRIBUTING.md#code-formatting))
* [ ] Tests have been added/updated (see
[here](https://github.com/jesseduffield/lazygit/blob/master/pkg/integration/README.md)
for the integration test guide)
* [ ] Text is internationalised (see
[here](https://github.com/jesseduffield/lazygit/blob/master/CONTRIBUTING.md#internationalisation))
* [ ] If a new UserConfig entry was added, make sure it can be
hot-reloaded (see
[here](https://github.com/jesseduffield/lazygit/blob/master/docs/dev/Codebase_Guide.md#using-userconfig))
* [ ] Docs have been updated if necessary
* [ ] You've read through your own file changes for silly mistakes etc

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Author: jesseduffield

.github/release.yml

@@ -21,6 +21,9 @@ changelog:
     - title: I18n 🌎
       labels:
         - i18n
+    - title: Performance Improvements 📊
+      labels:
+        - performance
     - title: Other Changes
       labels:
         - "*"

.github/workflows/ci.yml

@@ -184,7 +184,7 @@ jobs:
         with:
           mode: exactly
           count: 1
-          labels: "ignore-for-release, feature, enhancement, bug, maintenance, docs, i18n"
+          labels: "ignore-for-release, feature, enhancement, bug, maintenance, docs, i18n, performance"
   upload-coverage:
     # List all jobs that produce coverage files
     needs: [unit-tests, integration-tests]